如何在pyspark中将列合并为一个列在另一个列的顶部？

from pyspark.sql import SparkSession
from pyspark.sql.functions import concat_ws, lit

# 初始化 SparkSession
spark = SparkSession.builder.appName("example").getOrCreate()

# 创建一个示例 DataFrame
data = [("Alice", "New York"), ("Bob", "Los Angeles"), ("Charlie", "Chicago")]
columns = ["Name", "City"]
df = spark.createDataFrame(data, columns)

# 假设我们想将 "City" 列的值合并到 "Name" 列的顶部，并用换行符分隔
df = df.withColumn("Combined", concat_ws("\n", lit(""), "Name", "City"))

# 显示结果
df.show()

+------+------+----------------+
|   Name|    City|          Combined|
+------+------+----------------+
|  Alice|New York|Alice\nNew York|
|    Bob|Los Angeles|Bob\nLos Angeles|
|Charlie| Chicago|Charlie\nChicago|
+------+------+----------------+

df = df.withColumn("Name", df["Name"].trim())
df = df.withColumn("City", df["City"].trim())